import java.util.Scanner;

public class third {
    public static void main(String[] args) {
        System.out.println("请输入:");
        Scanner sc=new Scanner(System.in);
        String num=sc.next();
        int f=0;
        for(int i=0;i<(num.length()/2);i++){
            char charAt =num.charAt(i);
            char charAt2 =num.charAt((num.length()-1)-i);
            if(charAt!=charAt2){
                f=1;
                break;
            }
        }
        if(f==0){
            System.out.println("是回文");
        }else{
            System.out.println("不是回文");
        }
    }
}
